This book constitutes the refereed proceedings of the Third International Conference on Digital Economy, ICDEc 2018, held in Brest, France in May 2018. The conference was founded in 2016 to discuss innovative research and projects related to the support role of Information System Technologies in the digital transformation process, business innovation and e-commerce. The 15 papers presented in this volume were carefully reviewed and selected from 41 submissions. The theme of ICDEc 2018 was "Digital Economy: Emerging Technologies and Business Innovation". The papers were organized in topical sections named: digital marketing; e-banking and competitive intelligence; information system technologies; and e-learning, e-government and e-health.